Psychologists From New Zealand

"Some may find these conclusions frightening, and perhaps that's an appropriate reaction. But then again, maybe it’s not. For it is certainly possible to frame an ethic consistent with the Darwinian view of the world. Such an ethic might emphasize the virtue of being honest enough and courageous enough to acknowledge unflinchingly that there is probably no God, no afterlife, and no soul; that there is no objective basis to morality or higher purpose behind our suffering; that we are insignificant in a vast and impersonal cosmos; that existence is ultimately without purpose or meaning; and that the effects of our actions will ultimately fade away without trace. It is admirable to acknowledge these uncongenial truths, yet to struggle on as if life were meaningful and strive to make the world a better place anyway, without promise of eternal reward or hope of ultimate victory, and indeed for no good reason at all."

"Of course, nothing can be said to argue that people are morally obliged to accept this ethic, for to do so would be inconsistent with the ideas that inspired it in the first place. It is an ethic that will be adopted – if at all – by those who find a certain stark beauty in kindness without reward, joy without purpose, and progress without lasting achievement."

"As a result of high levels of male parental investment, humans evolved into a somewhat “androgynous” species - a species in which human females exhibit traits generally found only in males (e.g., competition for mates) and human males exhibit traits generally found only in females (e.g., the provision of parental care; choosiness about mates)."

"We are a species in which both sexes have their equivalents of the peacock’s tail. Indeed, when it comes to physical beauty, the usual sex difference has arguably been reversed: Females are the “showier” sex."

"For much of the 20th century, the blank slate view was the dominant view in the social sciences. With the popularization of sociobiology in the 1970s, however, evolutionary approaches to human behavior became the locus of an academic culture war between biologically minded thinkers and advocates of the traditional social science model."

"The pattern of sex differences found in our species mirrors that found in most mammals and in many other animals. As such, considerations of parsimony suggest that the best explanation for the human differences will invoke evolutionary forces common to many species, rather than social forces unique to our own. When we find the standard pattern of differences in other, less culture-bound creatures, we inevitably explain this in evolutionary terms. It seems highly dubious, when we find exactly the same pattern in human beings, to say that, in the case of this one primate species, we must explain it in terms of an entirely different set of causes — learning or cumulative culture — which coincidentally replicates the pattern found throughout the rest of the animal kingdom. Anyone who wishes to adopt this position has a formidable task in front of them. They must explain why, in the hominin lineage uniquely, the standard evolved psychological differences suddenly became maladaptive, and thus why natural selection “wiped the slate clean” of any biological contribution to these differences. They must explain why natural selection eliminated the psychological differences but left the correlated physical differences intact. And they must explain why natural selection would eliminate the psychological differences and leave it all to learning, when learning simply replicated the same sex differences anyway. How could natural selection favor extreme flexibility with respect to sex differences if that flexibility was never exercised and was therefore invisible to selection?"

"From a comparative perspective, we are a relatively monomorphic mammal, with relatively monomorphic minds."

"Human beings are an exception to many general rules in biology. In many species, female mate choice alone is important; in our species, male mate choice is important as well. In many species, males alone are showy and ornamented; in our species, females are as well. In many species, males alone compete for mates; in our species, females compete as well. In many species, males invest nothing other than sperm in their offspring; in our species, men typically invest a great deal. Not only are human beings exceptional in these ways, but they all tie together into a cohesive story."

"The idea that humans form pair bonds, and that males often invest in their young, has a long history in biological anthropology. Early incarnations of the idea were criticized for painting an overly simplistic picture, according to which “Man the Hunter” provisioned his dependent wife and children with meat in a stable nuclear family, suspiciously reminiscent of a 1950s-style Western family. However, with appropriate amendments and qualifications, the idea that pair bonding and biparental care are a central part of our evolutionary endowment appears to be viable."

"It is therefore a curious fact that our dominant mating system is more like the typical mating system of birds than that of most mammals, including our nearest relatives, the Great Apes."

"Our claim is not that pair bonding is humanity’s singular mating pattern. Our claim instead is simply that the pair bond is the most common setting for sex and reproduction in our species, that it has been for a long time, and that this has left a deep imprint on our evolved nature."

"Human beings are, by nature, the kind of animal that falls in love. The cross-cultural record also suggests that humans are also the kind of animal that commonly provides biparental care for its young. In 95% to 97% of mammalian species, only the females care for the young. We would no more expect males in these species to invest in their offspring than we would expect them to get pregnant or lactate. Humans are not like that."

"In some domains, women are more sexually selected than men; one could say in these cases that women have the larger “peacock’s tail.” An example can be found in the domain of physical attractiveness. Women are typically rated as better looking than men, by both men and women. The difference is plausibly a consequence of the fact that, although both sexes care about good looks in a mate, on average, men care somewhat more. This means that, since this sex difference first evolved, there has been a somewhat stronger selection pressure on women than men for physical attractiveness — the opposite of what we find in peacocks."

"If men in our evolutionary past did not invest in offspring, they would not have evolved strict mate preferences and thus women would be as drab as peahens. The fact that women are not as drab as peahens suggests a long history of male mate choice, which in turn suggests a long history of pair bonding and high male parental investment."

"Most male gorillas either have a harem or do not have a mate; in contrast, most men who have more than zero mates have only one. This means that, whereas only harem-holding male gorillas contribute to the gene pool of the next generation, most human males who contribute to the gene pool do so in the context of a pair bond. Consequently, our evolved sexual nature has been shaped more by pair bonding than by harem polygyny."

"However, the absence of perfect concealment does not imply the presence of active advertisement, and if fertility were advertised in humans, we would presumably not need to employ sophisticated experimental methods to demonstrate its detectability."

"To the extent that we accept this view, we effectively mistake ourselves for highly dimorphic animals such as peacocks or deer."

"Think about some of the highest status men in modern societies: sports stars, rock stars, politicians. At first glance, it might seem that these individuals provide further proof of men’s polygynous nature: They are often notorious for their sexual antics and infidelities (the famous scandal with Tiger Woods is a case in point)... However, the picture is not so simple. Many of these men are in the position where they have essentially an unlimited supply of potential sexual partners. Do all of them or even most of them eschew long-term relationships and opt instead for as many one-night stands and brief love affairs as possible? Sometimes, perhaps, but often they do not. These men — the most eligible bachelors, the highest status males in our species — often do what male chimpanzees never do: They fall in love and form long-term pair bonds."